"Generally speaking" don't work when architecture changes happen all the time that affect different tasks in different ways, but I'd put my money on that dual core with 2.0 gigabytes at 1 megahertz speed especially for the price of the former.

Well, a single core s754 is like 60-80% of a Pentium D, but gets obliterated by a Core 2 Duo (and moreso by the last Core 2 Duos). I'd go for a dual core Intel (preferably not Pentium 4 based) over a single core AMD s754, as the Intel dual core supportive chipsets also support DDR2-533 minimum which is better than the DDR400 AMD was stuck with until AM2 came out.